Slide 1 of 25 Copyright Pearson Prentice Hall Biology

Slide 2 of 25 Copyright Pearson Prentice Hall 17-4 Patterns of Evolution

Slide 3 of 25 Copyright Pearson Prentice Hall Macroevolution refers to large-scale evolutionary patterns and processes that occur over long periods of time. Six processes that lead to macroevolution.

17-4 Patterns of Evolution Slide 4 of 25 Copyright Pearson Prentice Hall Extinction 1. Extinction More than 99% of all species that have ever lived are now extinct. a. changing environments b. Mass extinctions

17-4 Patterns of Evolution Slide 5 of 25 Copyright Pearson Prentice Hall Adaptive Radiation 2. Adaptive Radiation the process by which a single species or a small group of species evolves into several different forms that live in different ways. Ex: Finches in Galapagos Islands Ex: animal diversity after dinosaur extinction

17-4 Patterns of Evolution Slide 6 of 25 Copyright Pearson Prentice Hall Adaptive Radiation Adaptive Radiation of Mammals ArtiodactylsCetaceans Perissod actyls Tubulidentates HyracoidsSireniansProboscideans Ancestral Mammals

17-4 Patterns of Evolution Slide 7 of 25 Copyright Pearson Prentice Hall Convergent Evolution 3. Convergent Evolution process in which unrelated organisms come to resemble one another is called convergent evolution due to similar environments Ex: sharks, dolphins, seals, and penguins.

17-4 Patterns of Evolution Slide 8 of 25 Copyright Pearson Prentice Hall Coevolution 4. Coevolution The process by which two species evolve in response to changes in each other over time– the organisms are closely connected due to ecological interactions Flowers and bees

17-4 Patterns of Evolution Slide 9 of 25 Copyright Pearson Prentice Hall Punctuated Equilibrium 5. Punctuated or Gradual change Darwin felt that biological change was slow and steady, an idea known as gradualism.

17-4 Patterns of Evolution Slide 10 of 25 Copyright Pearson Prentice Hall Punctuated Equilibrium Punctuated equilibrium is a pattern of evolution in which long stable periods are interrupted by brief periods of more rapid change.

17-4 Patterns of Evolution Slide 11 of 25 Copyright Pearson Prentice Hall Developmental Genes and Body Plans 6. Developmental Genes and Body Plans Hox genes – master control genes of all living organisms Small changes in the activity of control genes can affect many other genes to produce large changes in adult animals a.Timing in cell differentiation

17-4 Patterns of Evolution Slide 12 of 25 Copyright Pearson Prentice Hall Developmental Genes and Body Plans Evolution of Wings in Insects Ancient InsectTwo Types of Modern Insects

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Slide 14 of 25 Copyright Pearson Prentice Hall 17-4 Darwin's species of finches were very similar but different in beak size and feeding habits. This is an example of a.convergent evolution. b.coevolution. c.adaptive radiation. d.stabilizing selection.

Slide 15 of 25 Copyright Pearson Prentice Hall 17-4 A slow steady change in a particular line of descent is called a.coevolution. b.gradualism. c.punctuated equilibrium. d.convergent evolution.

Slide 16 of 25 Copyright Pearson Prentice Hall 17-4 Master control genes are called a.hox genes. b.developmental genes. c.embryonic genes. d.regulatory genes.

Slide 17 of 25 Copyright Pearson Prentice Hall 17-4 Some evidence suggests that species do not change much over long periods of time and then undergo relatively short periods of rapid speciation. This kind of change is called a.coevolution. b.genetic equilibrium. c.adaptive radiation. d.punctuated equilibrium.

Slide 18 of 25 Copyright Pearson Prentice Hall 17-4 Fossil evidence shows that mass extinctions a.ended the existence of many species in a short period of time. b.occurred mainly when the dinosaurs disappeared. c.require an asteroid strike to occur. d.caused convergent evolution among animals.

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